How to get an IntProperty to update a function?
Code Fix

Made some changes to get this running.  Pretty sure the HORRIBLE register_module is being phased out, wrote a register and unregister method with no parameters. This is what an addon expects to see, and is called when an addon is enabled.

The update method is defined on the property update=method without the braces, ie it's the function definition, not the result of the called method (method()).  The update method has two parameters, self and context.  The self in this case will the the scene instance, since the property is defined on the Scene class.  

Lastly it's standard to use xxx_yyy for method and property names, and XxxYyy for class names.

import bpy
from bpy.props import IntProperty

class UIPanel(bpy.types.Panel):
    bl_label = "Export EDL"
    bl_space_type = "SEQUENCE_EDITOR"

    bl_region_type = "UI"

    def draw(self, context):
        layout = self.layout
        scn = context.scene
        layout.label(text=" Select Video Channel: ")
        layout.prop(scn, "my_int", icon='BLENDER', toggle=True)


def change_channel(self, context):        

    active_channel = self.my_int    
    print("Active Channel: "+str(active_channel))

    sed = self.sequence_editor
    # if active strip isn't in active_channel set to None.
    if getattr(sed.active_strip, "channel", -1) != active_channel:
        sed.active_strip = None

    sequences = sed.sequences_all
    # select all strips in active channel
    for strip in sequences:
        strip.select = strip.channel == active_channel  

#    Registration
def register():
    bpy.utils.register_class(UIPanel)
    bpy.types.Scene.my_int = IntProperty(
        name = "Channel", 
        description = "Select Channel for Video Export",
        min=1,
        max=32,
        default=1,
        update=change_channel)
def unregister():
    bpy.utils.unregister_class(UIPanel)    

if __name__ == "__main__":
    register()